Electromagnetic relay with dashpot type time delay device



Nov. 8, 1966 A. M. COHEN 3,284,733

ELECTROMAGNETIC RELAY WITH DASHPOT TYPE TIME DELAY DEVICE Filed Feb. 18, 1964 2 Sheets-Sheet 1 FIG. FY612 A. M. COHEN Nov. 8, 1966 ELECTROMAGNETIC RELAY WITH DASHPOT TYPE TIME DELAY DEVICE Filed Feb. 18, 196'} 2 Sheets-Sheet 2 F IG. 5

United States Patent 0 3,284,733 ELECTROMAGNETIC RELAY WITH DASHPQT TYPE TIME DELAY DEVICE Arthur M. Cohen, Sturgis Highway, Westport, Conn. Filed Feb. 18, 1964, Ser. No. 345,735 8 Claims. (Cl. 33561) The present invention relates to the construction of a time delay actuator.

There are many instances where an action is to be performed a predetermined period of time after the appearance of a given signal. One of the most common types of such action is the modification of an external electrical circuit by the closing or opening of relay contacts in that circuit. Many constructions have been disclosed in the past for accomplishing these results, in some of which the timing is accomplished by adjustably damping the movement of a solenoid core within a solenoid. When the solenoid is energized and the core has moved thereinto to a predetermined degree the external magnetic field is so modified by the core as to attract an external armature, the movement of the latter from its normal to its attracted position effecting the desired external circuit modification. Devices of this type have the advantage of simplicity and small size, and under optimum conditions provide a reasonable degree of timing accuracy, but they suffer from the disadvantage that the magnetic pull on the external armature increases gradually, thus causing the external armature to move to its attracted position in a gradual rather than in an instantaneous manner. by the armature are similarly moved gradually rather than instantaneously, and this gives rise to arcing and pitting of the contacts, thus greatly limiting the amount of external circuit power which can be handled by the device and, even under optimum conditions, appreciably reducing the life of the device. This problem is intensified, and certain additional problems also present themselves, when the solenoid coil is energized by alternating rather than direct current. Under those circumstances actual chattering of the armature is a common occurrence.

It has also proved to be difficult, in time delay devices of the type under discussion, to provide for reliable accuracy of timing operatiion and at the same time keep the operating structure simple and inexpensive. A particularly troublesome area, from a mechanical point of view, resides in the mounting of the core for movement into and out of the solenoid with a minimum of dislocative friction, and the connection of the core to the dampv ing device.

It is a prime object of the present invention to provide a time delay actuator in which a member such as a core is adapted to be moved from one position to another in response to the energization of a coil, the movement of the member being damped to provide a controllable time delay mechanism, and in which the member moves over the last portion of its range of movemnet in a positive and rapid manner, thereby to cause the desired external effect to be accomplished by snap action. A second main objective is to provide a simple construction for a device of the type under discussion in which chattering is avoided and the opening and closing of electrical contacts is accomplished in a manner such as to minimize arcing and pitting and greatly extend the life of the contacts. A further object is to provide a device which can be A.C. energized without experiencing the deleterious effects usually accompanying that type of energization. An additional object is to so arrange the parts involved in measuring and producing the adjustable time delay as to minimize friction, increase dependability and accuracy, and minimize cost.

As a result the electrical contacts controlled To these ends a core is provided which is biased to a position outside or remote from an electromagnet coil and which is adapted to be moved into or closer to that coil when the coil is energized. The core is directly connected to the piston of an adjustable dashpot. The dashpot is specially designed so as to permit the attainment of the above objectives. Thus, during themajor portion of the core movement after the coil is energized the core is strongly damped by the dashpot, but when the core is almost at its final coil-attracted position the space between the dashpot piston and the dashpo-t cylinder is vented, thus permitting the core to move quite rapidly over the last fraction of its range of movement to its attracted position. The external armature which is magnetically acted upon by the coil-core combination is so designed as to be moved to its actuated position with a snap action when the core thus moves rapidly through the last fraction of its range of movement. Particularly when A.C. energization is involved, a permanent magnet fixedly mounted on the structure may be utilized to facilitate the snap action movement of the armature to its actuated position and to retain the armature in that position despite fluctuations in the magnetic field emanating from the coil-core combination attendant upon the A.C. energization of the coil. Moreover, the dashpot is so designed that an appreciable volume of fluid is trapped between the piston and cylinder of the dashpot when the core is in its stand-by or unattracted position, thereby rendering the core-piston combination easier to start into movement and eliminating undesirable resonance eftectsjthe latter being particularly troublesome when the coil is A.C. energized. Resonance effects on A.C. energization are further minimized through a special design of the core, particularly involving the addition of an inertia member thereto. A resistor of appreciable magnitude is connected in series with the coil in order to make the pull of the coil on the core more constant as the core moves into the coil. This resistor, if it is characterized by a negative temperature coefiicient of resistance, can also minimize sensitivity of the timing action to variations in temperature. The structure is simplified, and frictional resistance to the movement of the core is minimized, by providing a novel bearing arrangement for the core which is structurally integrated with the mounting arrangement for the damp ing dashpot.

To the accomplishment of the above, and to such other objects as may hereinafter appear, the present invention relates to the construction of a time delay actuator as defined in the appended claims and as described in this specification, taken together with the accompanying drawmgs, in which:

FIG. 1 is a cross sectional view of a first embodiment of the present invention, specially designed for DC. energization, the parts being shown in the position which theyassume when the coil is not energized;

BIG. 2 is a view similar to FIG. 1 but showing the position of the parts when the coil is energized and the device has timed out;

FIG. 3 is a three-quarter perspective view, on a reduced scale, of the device of FIG. 1; and

FIGS. 4, 5 and 6 are views similar respectively to FIGS. 1, 2 and 3, but illustrating an alternative embodiment specially designed for A.C. energization.

Turning first to the D.C.-energized embodiment of FIGS. 13, the relay comprises a base plate 2 having an upstanding arm 4 on which bracket 6 is mounted, the bracket carrying at its upper end a stack of relay contacts generally designated 8 and comprising upperand lower contact arms 1%) and 12 and intermediate contact arm 14. Pivotally mounted on the upper end of the upstanding arm 4 is an armature 16 having a rearwardly extending end 18 to which biasing spring 20 is connected, the other end of the biasing spring being attached to lug 22 extending from the bracket 6. The effect of the spring 28 on the armature 16 is to cause it to pivot in a counterclockwise direction. The armature 16 carries a plate 24 through which the tip of the intermediate contact arm 14 extends, the arrangement being such that when the armature 16 is in its normal biased position, as shown in FIG. 1, pivoted in a counterclockwise direction, the plate 24 is raised and the intermediate contact arm 14 is separated from the lower contact arm 12 and is moved into engagement with the upper contact arm 10.

Mounted on the base plate 2 beneath that portion of the armature 16 extending to the right of the arm 4 is a solenoid coil 26 with electrical leads 28 and 38 extending therefrom. A resistor 32 is preferably electrically connected in series with the coil 26. The coil 26 is wound on form 34 having a central axial passage 36, and a ring 38 is secured to the upper end of that passage.

A core of magnetic material, generally designated 40, is adapted to move into and out of the axial passage 36 via the lower end thereof, and the support plate 2 is provided with an opening 42 registering with the passage 36 through which the core 40 can pass. A spring 44 is compressed between a shoulder 46 on the core 40 and the ring 38 at the top of the passage 36, the spring 44 thus biasing the core 40 downwardly to a position essentially outside the passage 36. The core 40 has a lower hollow section 48 and an upper narrow section 50, the shoulder 46 being formed between those sections. A stop ring 52 is secured to and extends radially out from the lower portion of the lower core section 48.

A ferrule 54 lines the inner surface of the opening 42 in the base plate 2, and that ferrule has a depending skirt 56 to which the cylinder 58 of a damping dashpot generally designated 59 is secured in a position coaxial with the passage 36. Sealingly slidable within the cylinder 58 is a piston 60 having a depending skirt 62. The central portion of the horizontally extending wall of the piston 60 is apertured, at 64, and a ferrule 66 is received therein, the depending portion 68 of the ferrule carrying a valve casing 70 with an opening 72 in its bottom wall. Received within the casing 70 is a ball 74 having a rod 76 extending up through the ferrule 66 with appreciable clearance therearound, the upper end of the rod being received within the hollow lower core section 48 and being secured therein by means of plug 78 which is fixed both to the rod 76 and to the inner surface of the core section 48. A spring 80 is received within the valve casing 70 and biases the ball 74 upwardly into sealing engagement with seat 82, the ball 74 having an appreciable degree of vertical axial play within the casing 70. The bottom wall 84 of the cylinder 58 is provided with an opening 86 within which a screw-threaded adjustable throttling valve 88 is mounted. A casing 90 is secured to the base plate 2 and surrounds the dashpot 59, the adjustable throttling valve 88 being accessible at the end of the casing 90 and preferably being provided with a removable protective cap 92.

The side wall of the dashpot cylinder 58 is provided, at a point well up along its length, the precise location of which will be set forth hereinafter, with a vent opening 94.

The inner surface of the ferrule 54 preferably engages the outer surface of the lower core section 48 with a free-sliding fit, thereby acting as a bearing for the core 40 as it moves between operative positions. In order to reduce friction between the core 40 and the ferrule 54 to a minimal value while at the same time providing a proper bearing for the core 40 in its movement, the external surface of the'lower core section 48 may be coated with a suitable polyester resin such as the one sold by Du Pont Corporation under the trade name Mylar.

. This coating may be applied in the form of a tape wound tightly about the lower core section 48. The dashpot piston 60 to which the core 40 is secured also functions to maintain the core 40 in proper alignment.

As shown in FIG. 1, when the coil 26 is not energized the spring 44 moves the core 40 down until the skirt 62 of the dashpot piston 60 engages the bottom wall 84 of the dashpot cylinder 58. The armature 16 is in its counter-clockwise unactuated position, and the contact arms 14 and 10 are in engagement. When the coil 26 is energized an electromagnetic field is produced which is, at the upper end of the coil 26, insufiicient to cause the armature 16 to move against the action of its biasing spring 20. However, the core 40 is attracted and starts to move up into the passage 36. The core 40, thus moving, pulls the ball '74 into firm sealing engagement with the seat 82 and then pulls the piston 60 up with it. This movement is resisted by the dashpot 59, and the degree to which it is resisted is determined by the rapidity with which air can enter the space between the piston 60 and the bottom cylinder wall 84 via the throttling valve 88. Thus the setting of the throttling valve will control the speed with which the piston 40 moves upwardly. That speed will also be a function of the energization of the coil 26 and, at any given instant, by the opposing and increasing force exerted by the spring 44 as it is compressed.

Another factor controlling the force exerted by the coil 26 on the core 40 is the size of those sections of the core received within the coil. By making the upper section 50 of the core narrow, that upper section initially being substantially completely within the coil 26 and the lower core section 48 initially being substantially outside the core 26, the magnetic force exerted on the core 40 by the coil 26 is made non-linear with variations in line voltage, thereby making the timing effect less dependent upon such voltage variations. In addition, the magnetic pull exerted on the core as it goes up will increase, for a given coil energization, because more and more of the wider section 48 of the core comes inside the coil 26, thus making the pull on the core more uniform with change in core position by balancing the increased push in the opposite direction exerted by the spring 44 as it becomes compressed. Moreover, by making the upper section 50 of the core 40 narrower, the weight of the core is reduced and hence the operation of the device becomes less sensitive to vibration, shock, or the particular attitude in which the device may be positioned.

Because the piston 60 has a skirt 62 of appreciable length, the space between itself and the bottom wall 84, when the piston first starts to move, has an appreciable volume. Hence the piston 60 will start to move more readily than if it were exceedingly close to the bottom cylinder wall 84' with only a minimal inertia space therebetween.

As the core 40 moves up into the passage 36 the intensity of the magnetic field active ,on the armature 16 increases, but it is only when the core 40 is substantially in its uppermost position, as shown in FIG. 2, with the tip of the upper core portion 50 extending slightly upwardly from the coil 26, that the magnetic pull on the armature 16 is sufficient to counterbalance the action of the biasing spring 20. Engagement of the stop ring 52 with the underside of the ferrule 54 determines this final position of the core 40 (see FIG. 2). When the armature 16 is thus moved against the action of the spring 20 it pivots in a clockwise direction, the plate 24 is moved down, and the contact arm 14 is moved out of engagement with the upper contact arm 10 and into engagement with the lower contact arm 12. Thus the time that it takes the core 40 to move from its position in FIG. 1 to its position in FIG. 2 constitutes the time delay between the energization of the coil 26 and the shifting of the contact arm 14 from the contact arm 10 to the contact arm 12. The duration of this time delay can be adjusted through the setting of the throttling valve 88.

In order to ensure that the armature 16 moves to its actuated position quickly and that it remains firmly in that actuated position, means are provided to cause the core 40 to move decisively and rapidly over the last fraction of its travel. This means is constituted by the vent 94 in the cylinder wall 58. That vent is blocked by the piston skirt 62 during most of ahe movement of the piston 60. However, when the core 40 is almost at its upper limit of movement the lower edge of the piston skirt 62 will expose the inner end of the vent 94- to the space between the piston 60 and the cylinder end wall 84. Thus air will be permitted to enter that space freely through the vent 94, the vent by-passing the throttling valve 88, and as a result the damping action of the dashpot 60 is greatly reduced.

The speed with which the core 40 moves upwardly is determined in part by the current flowing through the coil 26, and this will in turn be dependent not only upon the signal applied thereto but also upon the resistance of the coil circuit. That resistance will normally increase with temperature, and hence the timing action of the device will tend to vary with temperature. The resistor 32 is provided, in this D.C. embodiment, to minimize that effect, said resistor having a negative temperature coeflicient of resistance, thereby making the overall resistance of the coil circuit more constant with temperature changes.

When the coil 26 is de-energized the spring 44 pushes the core 40 downwardly. The first result of this movement is to move the ball 74 downwardly within the valve casing 70, compressing spring 80. This provides a vent opening through the piston 60, so that the piston will then move downwardly with the core 40 with only a minimal damping effect. Thus reset times as low as l/ th of a second can be achieved.

The A.C. energized embodiment of FIGS. 46 is basically the same as the D.C. energized embodiment of FIGS. 1-3, and function-s in substantially the same manner. Accordingly the structural parts of the A.C. embodiment of FIGS. 46 which have corresponding parts in the D.C. embodiment of FIGS. l-3 are identified by the same reference numerals as have previously been employed.

There are three major differences between the A.C. and D.C. embodiments, all related to special problems which arise from A.C. energization.

In the first place, the core 40' is differently designed. Its upper portion 50 is somewhat wider a'han the upper core portion 50 of the embodiment of FIGS. 13. At its upper end it is counterbored, at 96, and a ring 98 of copper or other conductive material is placed therein and is secured in place by pin 100. The lower core portion 48 is solid rather than hollow, and the stop ring 52 secured thereto is of substantial mass, thereby adding to the inertia of the core 40'.

In the second place a bracket 102 is secured to the upper end of the arm 4, and it carries a permanent magnet 104 located beneath the right hand end of the armature 16. This permanent magnet 104 is not strong enough to cause the armature 16 to pivot in a clockwise direction against the action of the spring 20, nor is it strong enough, unaided, to retain the armature 16 in its actuated clockwise position against the action of the spring 20. It does, however, add a magnetic pull on the armature 16 which is sufficient, once the armature 16 has moved to its actuated clockwise position in engagement With the permanent magnet 104, or substantially so, to retain the armature 16 in actuated position even though the magnetic pull exerted thereon by the coil 26 and core 40' should fluctuate. The permanent magnet 104 thus assists in effecting snap action movement of the armature 16 to its actuated position and effectively prevents chattering of the armature 16, or movement thereof from its actuated position, under the influence of vibration, shock, or fluctuations resulting from the A.C. energization of the coil 26. The presence of the copper ring 98 also contributes to maintaining the armature 16 in actuated position, since the ring 98 produces an induced magnetic field degrees out of phase with the field produced by the A.C. energization of the winding 26, thereby holding the armature 26 in actuated position during those short intervals of time when the alternating flux produced by the coil 26 has an insufficient magnitude to so do unaided.

The relatively massive nature of the core 40 prevents resonant vibration thereof in response to A.C. energization of the coil 26, and such resonant vibrations are further minimized, particularly at the beginning of movement of the core 40 toward its upper position, by the fact that the piston 60 'has an extended skirt 62, thereby trapping an appreciable volume of air between itself and the cylinder end wall 84. This makes for a softer pneumatic spring action, tending to eliminate resonance effects, as well as permitting the core 40' to move upward more readily at the beginning of its movement, the latter also being true in the case of the D.C. embodiment, as has been explained.

In the third place, the resistor 32 utilized in the A.C. embodiment may perform an additional function. The inductance of the winding 26 Will increase as the core 40 moves upwardly and hence the impedance of the winding circuit will tend to increase and the amount of current flowing therethrough will tend to decrease. This has the effect of reducing the magnetic pull on the core 40' as it moves upwardly, an undesirable effect, particularly in view of the fact that the downward pressure of the core-biasing spring 44 increases as the core moves upwardly. For best timing results. the pull of the solenoid on the core 40 should be only slightly greater than the push of the spring 44. In order to use a practical biasing spring, the current through the winding 26 should not decrease too rapidly with core movement. Accordingly the resistor 32 in series with the winding 26 is made sufficiently large so that the change in coil inductance resulting from core movement gives rise to only a minimal change in coil circuit impedance. The magnitude of resistance of resistor 32' will, of course, depend upon such factors as the inductance of the coil 26, the strengths and dynamic characteristics of the springs employed, and the magnitudes of the signals involved, but the principles involved will be clear to those skilled in the art, and the selection of a particular resistance value will be a matter of engineering computation well within the ability of those normally skilled in the art.

The time delay actuators here disclosed are simple and inexpensive, and the moving parts thereof are all sturdy and reliable. Timing ranges from 0.1 second to 60 seconds are available in standard units, with special models capable of giving timing up to 30 minutes. The timing accuracy is within five percent at rated voltage and constant temperature. Reset times as short as of a second are obtained. Commercial devices are capable of use for from five to seven million operations without failure or loss of specified accuracy.

The design of the units are such that snap action results, with consequent minimization of contact deterioration and wear and greatly reduced sensitivity to vibrations or resonance produced by any cause.

The embodiments here specifically disclosed are designed to produce a time delay on energization of the windings. These devices can also be used to provide a time delay on de-energization by employing an auxiliary general purpose relay which, when its control circuit is de-energized, provides power to energize the units here disclosed.

While but a limited number of embodiments have been here disclosed, it will be apparent that many variations may be made therein, all within the scope of the instant invention as defined in the following claims.

I claim:

1. A time delay actuator comprising a support, an electromagnet coil thereon, a member operatively associated with said coil and adapted to be moved from first to second operative positions when said coil is energized, damping means operatively connected to said member for restricting the speed of its movement from said first to said second operative position, said damping means comprising a cylinder and a piston movable therein, connected to said member, and movable therewith between first and second operative positions, corresponding respectively to said first and second operative positions of said member, respectively close to and remote from an end wall of said cylinder, the space between said piston and said end wall being in'restricted fluid communication with a source of fluid, said piston having a skirt sealingly slidably engaging said cylinder and extending toward said end wall, thereby defining a space of appreciable volume between said piston and said cylinder, including said end wall, when said piston is in said first operative position.

2. The time delay actuator of claim 1, in which said member, when in said second operative position, operatively affects the external magnetic field produced by said electromagnet coil, a switch-actuating element in said external magnetic field, normally biased to a first operative position, and movable to a second operative position in response to magnetic pull exerted thereon, and a permanent magnet on said support and in operative magnetic association with said element, said'element, in moving from said first to second operative positions, moving closer to said permanent magnet, the magnetic attraction of said permanent magnet on said element when the latter is in its first operative position being less than the biasing force thereon.

3. A time delay actuator comprising a support, an electromagnet coil thereon, a member operatively associated with said coil and adapted to be moved from first to second operative positions when said coil is energized, damping means operatively connected to said member for restricting the speed of its movement from said first to said second operative position, said member comprising a core movable into and out of said c-oil from said first and second operative positions respectively, said core comprising first and second parts which respectively lead and trail as said core moves into said coil, at least a portion of said second part being outside said coil when said core is in its first operative position, said first part being narrower than said second part, and an inertia member operatively connected to said second part of said core.

4. A time delay actuator comprising a support, an electromagnet coil thereon, a member operatively associated with said coil and adapted to be moved from first to second operative positions when said coil is energized, damping means operatively connected to said member for restricting the speed of its movement from said first to said second operative position, said member, when in said second operative position, operatively affecting the external magnetic field produced by said electromagnet, a switch-actuating element on said support in said external magnetic field, normally biased to a first operative position, and movable to a second operative position in response to magnetic pull exerted thereon, and a permanent magnet on said support and in operative magnetic association with said element, said element, in moving from said first to second operative positions, moving closer to said permanent magnet, the magnetic attraction of said permanent magnet on said element when the latter is in its first operative position being less than the biasing force thereon.

5. A time delay actuator comprising a support, an electromagnet coil thereon, a member operatively associated with said coil and adapted to be moved from first to second operative positions when said coil is energized, damping means operatively connected to said member for restricting the speed of its movement from said first to said second operative position, said damping means comprising a cylinder and a piston movable therein, connected to said member, and movable therewith between first and second operative positions respectively close to and remote from an end wall of said cylinder, the space between said piston and said end wall being in restricted fluid communication with a source of fluid, said piston when in its first operative position being so located in said cylinder as to define a space of appreciable volume between itself and said end wall.

6. A time delay relay comprising a support, an electromagnetic coil on the upper side thereof having an axial passage, said support having a hole registering with said passage, a core movable through said hole between first and second operative positions respectively out of and in said coil passage and biased to saidfirst operative position, the edges of said hole engaging and being in sliding bearing relationship to said core, a dashpot on the lower side of said support in line with said hole and comprising a cylinder and a piston, means connecting said core and said piston for movement together, and a switch actuating element on said support above said coil, biased to a first operative position, and movable to a second operative position by magnetic attraction when said core is in its second operative position and said coil is energized, said piston moving with said core between first and second operative positions respectively close to and remote from an end wall of said cylinder, the space between said piston and said end wall being in restricted fluid communication with a source of fluid, said piston having a skirt sealingly slidably engaging said cylinder and extending toward said end wall, thereby defining a space of appreciable volume between said piston and said cylinder, including said end wall, when said piston is in said first operative position.

7. The time delay relay of claim 6, in which said core, when in said second operative position, operatively affects the external magnetic field produced by said coil, and a permanent magnet on said support and in operative magnetic association with said switch actuating element, said element, in moving from its first to its second operative position, moving closer to said permanent magnet, the magnetic attraction of said permanent magnet on said element when the latter is in its first operative position being less than the biasing force exerted thereon.

8. In the time delay actuator of claim 2, an inertia member operatively connected to said member.

References Cited by the Examiner UNITED STATES PATENTS 1,197,099 9/1916 Bliss 200-88 1,730,688 10/1929 Rippl 200-97 1,768,949 7/1930 Denison 20097 1,868,256 7/1932 Rippl 20097 2,036,176 3/1936 Hoban 200-97 2,308,660 1/1943 Kouyoumjian 200-97 X 2,456,463 12/1948 Starie 317--189 X 2,756,302 7/1956 Baltuch 317189 X 3,017,475 1/1962 Smith 200103 3,096,412 7/1963 Martin 200-87 3,179,396 4/1965 Bracken 200-34 X BERNARD A. GILHEANY, Primary Examiner.

T. D. MACBLAIN, Assistant Examiner. 

3. A TIME DELAY ACTUATOR COMPRISING A SUPPORT, AN ELECTROMAGNET COIL THEREON, A MEMBER OPERATIVELY ASSOCIATED WITH SAID COIL AND ADAPTED TO BE MOVED FROM FIRST TO SECOND OPERATIVE POSITIONS WHEN SAID COIL IS ENERGIZED, DAMPING MEANS OPERATIVELY CONNECTED TO SAID MEMBER FOR RESTRICTING THE SPEED OF ITS MOVEMENT FROM SAID FIRST TO SAID SECOND OPERATIVE POSITION, SAID MEMBER COMPRISING A CORE MOVABLE INTO AND OUT OF SAID COIL FROM SAID FIRST AND SECOND OPERATIVE POSITIONS RESPECTIVELY, SAID CORE COMPRISING FIRST AND SECOND PARTS WHICH RESPECTIVELY LEAD AND TRAIL AS SAID CORE MOVES INTO SAID COIL, AT LEAST A PORTION OF SAID SECOND PART BEING OUTSIDE SAID COIL WHEN SAID CORE IS IN ITS FIRST OPERATIVE POSITION, SAID FIRST PART BEING NARROWER THAN SAID SECOND PART, AND A INERTIA MEMBER OPERATIVELY CONNECTED TO SAID SECOND PART OF SAID CORE. 